<template>
  <div class="todo-footer">
    <label>
      <input type="checkbox" v-model="isCheckedAll" />
    </label>
    <span>
      <span>已完成{{ doneNum }}</span> / 全部{{ todoList.length }}
    </span>
    <button @click="deleteAllTodo" class="btn btn-danger">清除已完成任务</button>
  </div>
</template>
<script lang="ts">
import { defineComponent } from 'vue';
export default defineComponent({
  name: 'Footer'
})
</script>
<script lang="ts" setup>
import type { TodoData } from '@/App.vue';
import { computed } from 'vue';
const props = defineProps<{
  todoList: TodoData[],
  updateAllChecked: (val: boolean) => void
  deleteAllTodo(): void
}>()
// 计算已完成数量
const doneNum = computed(() => {
  return props.todoList.reduce((prev, item) => {
    if (item.isDone) {
      prev += 1
    }
    return prev
  }, 0)
})

const isCheckedAll = computed({
  get() {
    return props.todoList.every(item => item.isDone)
  },
  set(val) {
    props.updateAllChecked(val)
  }
})

// 清除已完成 
const deleteAllTodo = () => {
  props.deleteAllTodo()
}

</script>

<style lang="less" scoped>
/*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>